The Clinical Core provides the Projects with clinical, medical, neuropsychological and epidemiological data as well as clinical outcomes including diagnoses and significant life transitions. The Clinical Core is responsible for obtaining consents for study participation and for autopsy, and conducting diagnostic assessments. The specific aims are to clinically evaluate and follow a community-based sample recruited from the Medicare rooster (HCFA/CMS) for the area surrounding our clinic as well as volunteers who specifically consent to autopsy. All subjects are administered an in-person Clinical Core evaluation including assessments at baseline, and subsequent 12-month intervals and sooner if cognitive impairment is detected. Diagnostic work-ups (neuroimaging and blood testing) are obtained when clinically indicated. Case conferences are held to assign clinical outcomes for each subject at each wave. Clinical outcomes include: 1) Diagnosis of DSM-IV Dementia versus 'No Dementia', 2) for subjects with dementia, subtypes are diagnosed using standard criteria, 3) Intermediate States of Cognitive Impairment (Mild Cognitive Impairment, Clinical Dementia Rating 0.5, Amnestic Cognitive Impairment, Non Amnestic Cognitive Impairment), and 4) Documentation of significant life transitions (e.g., nursing home placement, death). The Clinical Core is also responsible for collecting follow-up medical and neuropsychologicat information for study subjects who no longer return for in-person evaluation. Data from the Clinical Core is used to determine eligibility of study participants for Projects and substudies.